Hitherto, various aminoglycoside antibiotics have been known to be produced by a variety of microorganisms. It has also been known to obtain aminoglycosides having incorporated the added substances into the molecule by the use of mutants of these microorganisms and by addition of intermediates which these mutants can not produce, such as deoxystrepamine, neamine, or their analogs. [Proc. Nat. Acad. Sci., U.S.A., 63: 198-204(1969), J. Antibiot., 26: 784-786(1973), British Pat. No. 1,480,374, J. Antibiot., 29: 532-535(1976)].
Further, it has been known through the study of biosynthetic route of aminoglycosides that naturally occuring intermediates can be converted into the aminoglycoside when the intermediate is added to the culture of the same producing organism. [J. Antibiot., 28: 573-579(1975), J. Antibiot, 29: 140-146(1976)].
However, it has not yet been known that novel and useful aminoglycosides having modified main chemical structure of natural aminoglycosides can be obtained by the application of the biosynthetic pathway of microorganisms to afford biochemical transformation, such as the 3', 4'-dideoxylation and C-methylation at its monosacchride constituents, which have hitherto been available only by chemical synthetic route.